Accident Details
The accident involved a Rockwell Grand Commander 690C Jetprop 840. The airplane was cleared for the approach and approximately eight minutes later was observed emerging from clouds, flying from west to east. Witnesses reported that the nose of the airplane dropped and the airplane subsequently impacted terrain in a near-vertical attitude. Impact forces and a post-impact fire destroyed the airplane. Examination of the airplane's systems revealed no anomalies.
Weather Conditions
Weather at the time of the accident was depicted as overcast with three to six miles visibility. An icing probability chart depicted the probability for icing during the airplane's descent as 76 percent. AIRMETS for moderate icing and instrument meteorological conditions had been issued for the airplane's route of flight. Another airplane in the vicinity reported light to moderate mixed icing. It could not be confirmed what information the pilot had obtained in a weather briefing, as a briefing was not obtained through a recorded source.
Weight and Balance
A weight and balance calculation revealed that the accident airplane was 1,000 pounds over gross weight at the time of departure and 560 pounds over gross weight at the time of the accident. It was estimated that the center of gravity was at or just forward of design limitations.
Probable Cause
The probable cause, as stated in the official findings, is the pilot's failure to maintain aircraft control during the approach resulting in an aerodynamic stall and subsequent impact with terrain. Contributing to the accident was the pilot's improper preflight planning and conditions conducive for structural icing.